(1) Field of the Invention
The present invention pertains to a manually operated reciprocating liquid pump dispenser that is removably connectable to a bottle containing a liquid. Manual operation of the dispenser simultaneously pumps the liquid from the bottle and pumps air from the exterior environment of the dispenser, mixes the liquid with the air to produce a foam, and dispenses the foam from the dispenser. More specifically, the pump dispenser of the invention includes a closure connector that provides a mechanism for venting the interior of the bottle to the exterior environment of the pump dispenser while avoiding leakage of the liquid from the bottle, and also incorporates a mechanism for locking the pump dispenser to prevent unintended pumping of the liquid from the bottle.
(2) Description of the Related Art
Manually operated, vertically reciprocated pump dispensers are those types of dispensers that are typically oriented vertically in use, and have a plunger at the top of the dispenser that is manually pressed downwardly to dispense the liquid contents of a bottle connected to the dispenser. The typical construction of such a dispenser includes an elongate pump housing and an elongate plunger that is received inside the pump housing for reciprocating movements between charge and discharge positions of the pump plunger in the pump housing.
The pump housing is inserted into the bottle neck opening of the bottle. A closure connector at the top of the pump housing removably secures the pump housing to the bottle neck. A dip tube connected at the bottom of the pump housing extends downwardly into the liquid in the bottle. The pump housing contains a liquid pump chamber and a check valve. The check valve controls the flow of liquid through the dip tube and into the pump chamber, and prevents the reverse flow of liquid.
The pump plunger has a tubular length with a liquid discharge passage extending through the center of the plunger. A liquid piston is mounted on the plunger and is received in the pump chamber for reciprocating movements. A dispensing head is provided at the top of the plunger. The dispensing head has a discharge outlet that communicates with the discharge passage of the plunger. A check valve in the liquid discharge passage controls the flow of liquid from the pump chamber and out through the dispensing head, and prevents the reverse flow of liquid.
A spring is positioned in the pump chamber. The spring biases the plunger upwardly to a charge position of the plunger relative to the pump housing. The upward movement of the plunger moves the piston upwardly in the pump chamber, which creates a vacuum in the pump chamber that draws liquid through the dip tube and into the pump chamber.
The pump plunger is manually depressed downwardly against the bias of the spring to a discharge position of the plunger relative to the pump housing. The downward movement of the plunger moves the piston downwardly in the pump chamber. The downward piston movement forces the liquid in the pump chamber through the liquid discharge passage of the plunger and out of the dispenser through the dispensing head.
In addition to the basic component parts of the manually operated, vertically reciprocated pump dispenser described above, many prior art pump dispensers are provided with a venting feature. The venting feature includes a vent opening that communicates the exterior environment of the dispenser with the interior of the bottle when the pump plunger is reciprocated in the pump housing. Air from the exterior environment of the dispenser is allowed to pass through the vent opening and enter the bottle interior to fill the volume in the bottle interior left vacant by the liquid being dispensed by the operation of the pump. Without such a vent opening, as liquid is dispensed from the bottle, a vacuum would be created in the bottle interior. The vacuum would eventually overcome the vacuum created by the pump piston moving to its charge position in the pump chamber, and prevent the pump from drawing liquid into the pump chamber. The increasing vacuum in the interior of the bottle could also possibly result in the inwardly collapsing of the bottle side walls. To overcome this problem, many prior art manually operated, vertically reciprocated pump dispensers are provided with constructions that allow air to vent into the interior of the bottle connected to the dispenser, while preventing liquid in the bottle from leaking out of the dispenser through the vent feature.
In addition to the above, many prior art manually operated, vertically reciprocated pump dispensers are provided with a locking feature. The locking feature would lock the plunger in its upward charge position relative to the pump housing or its downward discharge position relative to the pump housing. The locking feature would also close the liquid flow path through the pump. The locking feature thus prevents the unintended pumping of liquid from the bottle caused by unintended reciprocating movements of the pump plunger in the pump housing.
All of the above-described features that are often included in the typical construction of a manually operated, vertically reciprocated pump dispenser add to the number of component parts of the dispenser and add to the complexity of the assembly of the dispenser.
Manually operated, vertically reciprocated liquid pump dispensers have been developed that not only pump liquid from a bottle through the dispenser, but also pump air from the exterior environment of the dispenser through the dispenser, mixing the air with the liquid to generate a foam that is dispensed from the dispenser. These types of dispensers not only include all of the component parts of a dispenser required to draw liquid from the bottle connected to the dispenser and pump the liquid from the dispenser, but also include the additional component parts required to draw air from the exterior environment of the dispenser into the dispenser, mix the air with the liquid being pumped through the dispenser to generate the foam, and dispense the foam from the dispenser. Dispensers of this type that pump both liquid and air have even more component parts and an even more complex assembly than dispensers that pump only liquid. To provide a dispenser of this type with a venting feature and a locking feature would even further increase the number of component parts and the complexity of the assembly of the dispenser. To manufacture such a dispenser economically, it is necessary to provide a unique design of the dispenser that reduces the number of separate component parts of the dispenser and simplifies the dispenser construction.